I'd like to try doing a zoom into the Mandelbrot set for a talk that I'm doing in January. I know to use exponential on the magnification. Is there a rule of thumb for the spacing of key frames? Any helpful tips?

I'd like to try doing a zoom into the Mandelbrot set for a talk that I'm doing in January. I know to use exponential on the magnification. Is there a rule of thumb for the spacing of key frames? Any helpful tips?